Header hook-up - High block, low block ?????

Went to hook up a new to me 800 flex head and feeder house on R72 comes up way too high in the header opening. Don't know what model of combine this head was hooked up to previously. Am I on the right track thinking this a head that requires high mount hook up blocks on the feeder house? Or is there a way to adapt the head so I can just use the normal mounting blocks that are on my R72? Was getting dark so maybe I'll see the solution in the light of day but would appreciate any advice. I have a honeybee and a 420 pick up head that mount to existing feeder house so don't want to be switching blocks all the time.